<!doctype html>
<html>
<head>
    <meta charset="utf-8">
    <title>浮动与display:block化</title>
    <style>
        .ovh { overflow: hidden; }
        .red { color: #cd0000; }
        [hidden] { display: none; }
    </style>
</head>

<body>
<p id="first">这是一个没有设置<code>float</code>属性的按钮：</p>
<p class="ovh"><input type="button" id="btnShow" value="点击我显示display属性值"></p>
<p hidden="">此时，按钮的display属性值是：<span id="result" class="red"></span></p>
<p>点击下面的按钮让上面的按钮添加<code>float: left</code>的声明：</p>
<p><input type="button" id="btnAdd" value="上面的按钮添加float:left"></p>
<script>
  var btnShow = document.getElementById("btnShow"),
    btnAdd = document.getElementById("btnAdd"),
    result = document.getElementById("result"),
    first = document.getElementById("first");

  if (btnShow && btnAdd && result) {
    btnShow.onclick = function() {
      // 获得该按钮的display值
      var display = this.currentStyle? this.currentStyle.display: window.getComputedStyle(this, null).display;
      // 显示结果
      result.innerHTML = display;
      result.parentNode.removeAttribute("hidden");
      // repain fix IE7/IE8 bug
      document.body.className = "any";
    };

    // 设置浮动按钮的点击事件
    btnAdd.onclick = function() {
      btnShow.style["cssFloat" in this.style? "cssFloat": "styleFloat"] = "left";
      // 文字描述的变化
      this.value = "上面的按钮已经设置了float:left";
      btnShow.value = "再次点击我确认display属性值";
      first.innerHTML = first.innerHTML.replace("没有", '<del>没有</del>');
      // 结果隐藏
      result.parentNode.setAttribute("hidden", "");
      // 按钮禁用
      this.setAttribute("disabled", "");
    };
  }
</script>
</body>
</html>
